Hydrological Summary for the General Whilst temperatures remained below average, the high rainfall in May marked a sharp transition from an arid April. Recovery to warmer weather was delayed until the last week of May, making it the coldest April-May period in since 1951. The total May rainfall for the UK was 177% of average, and Wales saw its wettest May in a series from 1910. River flows were above average across much of the UK, exceptionally so in Wales, where the mean May outflow was the highest in a series from 1961. Despite the high May rainfall and accompanying reduction in soil moisture deficits (SMDs; which by month-end were below average except in Southern region), groundwater levels in the index boreholes continued to recede (with the exception of some in the west). Generally, reservoir stocks were close to average, with notable recoveries in Yorkshire (Washburn and Bradford Supply) and south-west England (Clatworthy and Wimbleball), whilst at Loch Thom and Teesdale below-average stocks persisted. With near-average groundwater levels in the south and east, and reservoir stocks healthy across England, Wales and Northern Ireland, the water resources situation is generally favourable entering the summer. June started with a dry spell, but only in western Scotland does this add to longer-term deficiencies. Rainfall May saw successive westerly bands of rain across the of the high flows across Wales resulted in record-breaking UK, interspersed by northerly airflows and showers May monthly mean flows on the Conwy, Dee, Teifi, Twyi, (sometimes wintry or thundery), before high pressure Tawe and Cynon (where flows were more than four times eventually dominated for a drier final week. The first the average) in series of 50 years or more (most notably of several low pressure systems (arriving on the 3rd) for its long series, the Welsh Dee on 21st-23rd). With both brought strong winds and outbreaks of heavy rain. It north and south Wales affected, the May outflow series for was unseasonably cold, with subsequent showers turning Wales (from 1961) saw a new daily maximum established to sleet and snow over high ground. The wet and often on the 21st (141% of the previous maximum recorded in cold conditions persisted, although with few notable daily May 2006). Elsewhere, record-breaking May monthly rainfall totals, except on the 8th when 98mm was recorded mean flows were also recorded on the Wensum and Dart at Treherbert, Mid Glamorgan. By the 13th, Wales, which (in series from 1966 and 1958, respectively). With high along with the south-west was bearing the brunt of the flows affecting several of the winter and spring months westerly systems, had already seen 129% of its average (December to May), mean flows for this six month period May rainfall. There was further rain affecting the north were notably or exceptionally high across England and of England on the 16th (bringing flooding to Langcliffe, Wales (the Weaver recording its highest mean over this Settle and Giggleswick, North Yorkshire) and on the 20th timeframe in a long series from 1937), and normal or (e.g. 103mm at Mickleden, Cumbria), and causing road and above normal in Northern Ireland and southern England. rail disruption in south Wales on the 21st. The final week of For a second consecutive year, the mean outflow from May was in marked contrast to the first few weeks, as high England across these six months ranked in the top five of pressure brought dry weather from the 24th to month-end. a series from 1961. With the persistent wet weather, rainfall was above average across most of the country (only north-west Scotland Groundwater was below average). More than twice the May average Although SMDs declined slightly during May, groundwater rainfall was recorded in the North East Scotland, Yorkshire, levels receded at all the Chalk index sites, except Dial Farm. Severn‑Trent and regions, and Wales Levels in Yorkshire and the majority of the southern (with 252% of average). The dry April and wet May, with England Chalk remained in the normal range. However, March having been closer to average, meant rainfall for levels in the Chilterns and East Anglia varied between May 2021 spring (March‑May) was near-average at the national scale. notably high at Washpit Farm and Frying Pan Lodge and the normal range at Redlands Hall. Levels also River flows fell in the Magnesian limestone and in the northern After starting the month below average, there were sharp parts of the Carboniferous (Alstonfield) and Jurassic increases in river flows (except in the south and east) (New Red Lion) limestone aquifers, generally ending on the 3rd which further increased on the 8th. This was the month notably to exceptionally high. Further south, especially marked in Wales, with new May peak flow levels rose in the Jurassic limestone at Ampney Crucis maxima established on the Tawe and the Cynon, both in (moving from normal to exceptionally high) and in the series from 1957 (the record on the latter more than one Carboniferous Limestone of south Wales (moving from and a half times that established in 1996). For the next below normal and notably low to in the normal range and fortnight, flows remained substantially above average, notably high at Greenfield Garage and Pant y Lladron, also rising markedly in the south and east. New daily respectively). In the Permo-Triassic sandstones, levels flow maxima were established on multiple rivers in Wales rose overall at Llanfair DC and Bussels No. 7A, and fell at (most notably 21st-23rd on the Welsh Dee for its long series Skirwith, Weir Farm and Nuttalls Farm; levels were above from 1937) and south-west England, and flooding on the normal to exceptionally high, with a new May maximum 21st suspended train services on the Conwy Valley line recorded at Weir Farm. Levels fell and were above normal (north Wales). Sustained recessions finally began on the for the time of year at Lime Kiln Way (Upper Greensand) 25th and continued to month-end. Overall, river flows and Royalty Observatory (Fell Sandstone). were in the normal range and above across England and Note: Due to unforeseen circumstances no data are available Northern Ireland. However, the duration and magnitude for Scotland. Rainfall . . . Rainfall . . . Rainfall accumulations and return period estimates Percentages are from the 1981-2010 average.

May Region Rainfall Apr21 – May21 Mar21 – May21 Dec20 – May21 Jun20 – May21 2021 RP RP RP RP United mm 120 140 224 625 1300 Kingdom % 177 101 2-5 97 2-5 112 5-10 115 20-35 England mm 111 122 172 500 1011 % 193 106 2-5 97 2-5 123 10-15 119 10-20 Scotland mm 110 145 285 758 1646 % 138 87 2-5 94 2-5 99 2-5 108 10-15 Wales mm 210 227 324 943 1787 % 252 134 5-10 114 2-5 133 40-60 126 40-60 Northern mm 116 141 215 571 1333 Ireland % 160 95 2-5 88 2-5 102 2-5 117 40-60 England & mm 125 137 193 561 1117 Wales % 204 111 2-5 100 2-5 125 10-20 121 15-25

North West mm 133 146 275 739 1605 % 186 102 2-5 114 5-10 125 20-35 131 >100 Northumbria mm 98 114 169 551 1063 % 177 97 2-5 92 2-5 132 30-50 122 15-25 Severn-Trent mm 117 130 171 478 929 % 206 113 2-5 100 2-5 128 10-15 119 8-12 Yorkshire mm 124 136 191 542 1079 % 233 119 2-5 107 2-5 133 15-25 128 20-30 Anglian mm 83 88 121 361 727 % 167 93 2-5 87 2-5 127 8-12 116 5-10 Thames mm 99 112 143 386 840 % 177 103 2-5 90 2-5 111 2-5 117 5-10 Southern mm 84 90 127 418 840 % 160 85 2-5 77 2-5 107 2-5 105 2-5 Wessex mm 120 137 177 480 982 % 199 115 2-5 95 2-5 109 2-5 111 2-5 South West mm 179 189 240 763 1443 % 239 124 5-10 97 2-5 121 5-10 117 8-12 Welsh mm 205 222 312 910 1730 % 252 135 5-10 114 2-5 134 40-60 126 50-80 Highland mm 98 155 353 838 1759 % 111 82 2-5 98 2-5 89 2-5 97 2-5 North East mm 133 168 237 595 1216 % 203 129 2-5 113 2-5 125 15-25 120 15-25 Tay mm 152 173 290 753 1574 % 194 113 2-5 106 2-5 110 5-10 117 15-25 Forth mm 113 129 220 644 1414 % 160 94 2-5 91 2-5 108 5-10 117 20-35 Tweed mm 118 135 209 644 1297 % 180 104 2-5 100 2-5 129 30-50 126 50-80 Solway mm 129 142 267 793 1829 % 156 83 2-5 90 2-5 108 5-10 123 >100 Clyde mm 91 117 276 851 2034 % 103 62 8-12 78 2-5 93 2-5 112 10-20 % = percentage of 1981-2010 average RP = Return period Important note: Figures in the above table may be quoted provided their source is acknowledged (see page 12). Where appropriate, specific mention must be made of the uncertainties associated with the return period estimates. The RP estimates are based on data provided by the Met Office and reflect climatic variability since 1910; they also assume a stable climate. The quoted RPs relate to the specific timespans only; for the same timespans, but beginning in any month the RPs would be substantially shorter. The timespans featured do not purport to represent the critical periods for any particular water resource management zone. For hydrological or water resources assessments of drought severity, river flows and/or groundwater levels normally provide a better guide than return periods based on regional rainfall totals. Note that precipitation totals in winter months may be underestimated due to snowfall undercatch. All monthly rainfall totals since January 2018 are provisional. 2 Rainfall . . . Rainfall . . . May 2021 rainfall December 2020 - May 2021 rainfall as % of 1981-2010 average as % of 1981-2010 average

250 170 200 150 170 130 140 110 120 90

80 70

% of average of % % of average of % 50 50 30 30

April - May mean temperature for England 12

11 C) The Hydrological Outlook provides an insight into future O hydrological conditions across the UK. Specifically it 10 describes likely trajectories for river flows and groundwater levels on a monthly basis, with particular focus on the next three months. 9 The complete version of the Hydrological Outlook UK can Temperature ( Temperature 8 be found at: www.hydoutuk.net/latest-outlook/

Period: from June 2021 7 1910s 1920s 1930s 1940s 1950s 1960s 1970s 1980s 1990s 2000s 2010s Issued: 08.06.2021 using data to the end of May 2021 December - May mean outflows for Wales 1000 The outlook for June and for the June–August period is for river flows to be normal to above normal in most parts 800 of the UK, the exception being the north west of Scotland and Northern Ireland where normal to below normal flows

) are likely in June. Groundwater levels in June, and for the -1

s 600 next three months, are likely to be normal to above normal 3 across most of the UK, the exception being the south east of 400 England where normal to below normal levels are expected. Flow (m 200

0 * For a grass cover 1960s 1970s 1980s 1990s 2000s 2010s

3 River flow . . . River flow . . .

December 2020 - May 2021

158 Coquet ●100 ● Mourne Bush Eden ●106 ●135 ●120 Tyne Tees Derwent ●128 135 ●118 ● Annacloy Leven ●132 123 Lune ● ●153 Derwent Ribble 135 Aire 141 ● Mersey ● Don 153 Conwy 141 ● ● Derwent ●156 Lud 133 Erch 151 182 ● ● ● 165 Wensum 139 142● ● 136 Dee Weaver 140 ● Witham 170 ● ● Trent ● Dove Stringside ●195 ●142 Severn ●184 Waveney Teifi 158 ●153 Avon ● 128 Yscir 174 Tywi 171 ● Coln ● ● 140 147 156 Lee 158 ● ● ● Colne ● ●166 Wye Tawe 120 Great Cynon Brue Avon ● 149 146 ● Stour Taw 111 Blackwater ● 117 ● Medway ●128 ●116 ● ●126 Itchen ●108 ●125 Tone 115 164 Coquet Warleggan ● Ouse 82 ● 141 Exe Stour 131 137 ● Kenwyn ●● ● Eden Dart Mourne Bush ●127 Tamar ●117 ●135 ●102 Tyne Tees © UKCEH (2021) © Crown copyright. Derwent ●128 179 ●78 ● Annacloy Leven ●141 182 Lune ● ●140 Derwent May 2021 Ribble 184 Aire 177 ● Mersey ● Don 167 Conwy 187 ● ● Derwent ●107 Lud 143 Key Erch 303 217 ● % of long−term average ● ● 110 Wensum 179 145● 25 ● 276 Dee Weaver 166 ● Witham 212 (record high/low when circled) ● ● Trent ● Dove Exceptionally high flow Stringside ●128 ●197 Severn ●80 Notably high flow Waveney Teifi 251 ●184 Avon Above normal ● 296 Yscir 94 Tywi 353 ● Coln ● ● 216 113 126 Lee Normal range 336 ● ● ● Colne ● ●416 Wye Tawe Below normal 124 Great Cynon Brue Avon ● 123 96 ● Stour Notably low flow Taw 101 Blackwater ● 136 ● Medway 294 163 ● Itchen ● ● ●107 ●107 Exceptionally low flow 252 Tone 117 Warleggan ● ● Ouse Based on ranking of the monthly flow* 233 Stour 123 291 Exe Kenwyn ●● ● Dart ●84 Tamar © UKCEH (2021). © Crown copyright.

River flows *Comparisons based on percentage flows alone can be misleading. A given percentage flow can represent extreme drought conditions in permeable catchments where flow patterns are relatively stable but be well within the normal range in impermeable catchments where the natural variation in flows is much greater. Note: the averaging period on which these percentages are based is 1981-2010. Percentages may be omitted where flows are under review. Note: Due to unforeseen circumstances no data are available for Scotland. 4 River flow . . . River flow . . .

River flow hydrographs *The river flow hydrographs show the daily mean flows (measured in3 m s-1) together with the maximum and minimum daily flows prior to June 2020 (shown by the shaded areas). Daily flows falling outside the maximum/minimum range are indicated where the bold trace enters the shaded areas. The dashed line represents the period-of-record average daily flow.

5 River flow . . . River flow . . .

6 Groundwater . . . Groundwater

Groundwater levels (measured in metres above ordnance datum) normally rise and fall with the seasons, reaching a peak in the spring following replenishment through the winter (when evaporation losses are low and soil moist). They decline through the summer and early autumn. This seasonal variation is much reduced when the aquifer is confined below overlying impermeable strata. The monthly mean and the highest and lowest levels recorded for each month are calculated with data from the start of the record to the end of 2017. Note that most groundwater levels are not measured continuously and, for some index wells, the greater frequency of contemporary measurements may, in itself, contribute to an increased range of variation. 7 Groundwater . . . Groundwater

8 Groundwater . . . Groundwater

Key Monthly rank/Period of record 1/25 (record high/low when circled) Exceptionally high levels Notably high levels Above normal ● Normal range Feddan Junction Below normal Notably low levels Exceptionally low levels

Aquifer Easter Lathrisk Chalk ● Jurassic limestone Permo Triassic sandstones Royalty 27/32 Observatory ● Magnesian limestone Devonian/Carboniferous limestone/sandstone Newbridge ● Annan Killyglen 22/36 ● Skirwith ● Aycliffe 41/42 ● ●41/42

Wetwang 21/50 Brick ● Dalton House 34/39 63/133 Holme Farm ● ● ●28/43 Aylesby Alstonfield New Red Washpit Llanfair 49/50 41/46 Lion Farm D.C. ● Weir Farm ● 37/58 ●37/37 ● ●66/72 Nuttalls Frying Pan 37/46 43/49 ● Farm Redlands ● Lodge Hall Dial 39/52 33/57 Farm Ampney ● ● Greenfield Garage Crucis 103/135 Pant y ● Therfield 18/28 Lladron 62/63 Stonor Rectory ● ● 45/61 Park 28/89 ● 24/26 ● ● Rockley West 44/78 Chipstead 14/53 Tilshead ● 44/51 Little Woodyates ● ● Bucket Manor 23/77 Houndean Farm 39/126 51/186 16/45 Bussels 41/52 ● ●● ● 38/50 40/79 Westdean No.3 No.7a ● ● 14/48 Chilgrove ● Lime ● Compton House Kiln Ashton House Way Farm © BGS NERC 2021

Groundwater levels - May 2021 The calculation of ranking has been modified from that used in summaries published prior to October 2012. It is now based on a comparison between the most recent level and levels for the same date during previous years of record. Where appropriate, levels for earlier years may have been interpolated. The rankings are designed as a qualitative indicator, and ranks at extreme levels, and when levels are changing rapidly, need to be interpreted with caution. Note: Due to unforeseen circumstances no data are available for Scotland. 9 Reservoirs . . . Reservoirs . . . Guide to the variation in overall Comparison between overall reservoir stocks for England and reservoir stocks for England and Wales Wales in recent years

Percentage live capacity of selected reservoirs at end of month

Capacity 2021 2021 2021 May Min Year* 2020 Diff Area Reservoir (Ml) Mar Apr May Anom. May of min May 21-20 North West N Command Zone • 124929 100 85 86 6 50 1984 61 25 Vyrnwy 55146 99 95 99 11 69 1984 80 19 Northumbrian Teesdale • 87936 82 74 74 -11 62 2020 62 12 Kielder (199175) 93 89 96 5 85 1989 85 11 Severn-Trent Clywedog 49936 98 99 99 2 83 1989 91 8 Derwent Valley • 46692 97 83 92 5 56 1996 68 24 Yorkshire Washburn • 23373 83 76 87 1 71 2020 71 17 Bradford Supply • 40942 91 84 97 12 68 2020 68 29 Anglian Grafham (55490) 92 96 92 -2 72 1997 94 -2 Rutland (116580) 96 96 95 3 75 1997 94 1 Thames London • 202828 97 96 91 -3 83 1990 92 -1 Farmoor • 13822 98 96 96 -2 90 2002 99 -3 Southern Bewl 31000 92 90 90 2 57 1990 94 -4 Ardingly 4685 100 99 100 1 89 2012 96 4 Wessex Clatworthy 5662 100 89 100 14 67 1990 78 22 Bristol • (38666) 97 89 89 0 70 1990 85 5 South West Colliford 28540 94 86 87 1 52 1997 80 7 Roadford 34500 97 91 93 9 48 1996 86 7 Wimbleball 21320 100 85 98 6 74 2011 81 16 Stithians 4967 98 89 88 0 66 1990 84 3 Welsh Celyn & Brenig • 131155 97 98 100 3 79 2020 79 21 Brianne 62140 97 88 93 -2 82 2020 82 11 Big Five • 69762 97 87 92 2 70 1990 74 18 Elan Valley • 99106 96 90 98 5 76 2020 76 22

Scotland(E) Edinburgh/Mid-Lothian • 97223 98 93 92 2 52 1998 82 10 East Lothian • 9317 100 99 100 3 84 1990 97 3 Scotland(W) Loch Katrine • 110326 98 88 85 -2 66 2001 79 6 Daer 22494 99 87 85 -4 69 2020 69 16 Loch Thom 10721 88 72 73 -18 70 2020 70 3

Northern Total+ • 56800 96 89 91 6 69 2008 75 16 Ireland Silent Valley • 20634 93 84 87 5 56 2000 70 17

( ) figures in parentheses relate to gross storage • denotes reservoir groups *last occurrence + excludes Lough Neagh

Details of the individual reservoirs in each of the groupings listed above are available on request. The percentages given in the Average and Minimum storage columns relate to the 1988-2012 period except for West of Scotland and Northern Ireland where data commence in the mid-1990s. In some gravity-fed reservoirs (e.g. Clywedog) stocks are kept below capacity during the winter to provide scope for flood attenuation purposes. Monthly figures may be artificially low due to routine maintenance or turbidity effects in feeder rivers. © UKCEH (2021). 10 Location map . . . Location map

Shetland Isles

# Naver He Orkney lm sda Isles # Inver le # # Oykel

Feddan Western #E w Isles e Junction

n # ro ! e n Car si # ro os e # Highland North East # # L ev D Ythan Scotland s s y # Ne Spe Don # Tay

Dee # Forth

B er Clyde # Nevis vi # e Tweed Northumbria Solway Ta#y Northern Ireland Earn # North " Katrine Easter ! West Yorkshire England Luss # # Lathrisk Forth East Leven Lothian G West # yne Cl Lothian T " Thom # y Whiteadder de " # #! Royalty Observatory Midlands Anglian d " wee Edinburgh/ T Welsh Nith G Mid-Lothian Coqu et # " Daer Thames #Bush Braden # Kielder G South Faughan # Lower Cr ! Newbridge Wessex # e West e ! Annan Southern Bann # # Tyne England # ! # Killyglen # E Mourne d South e n Tyne #Cam owen # ! Aycliffe a#n Derwent Skirwith # ! Lag " " " # Northern Haweswater & es # Teesdale Te Annacloy Command Thirlmere D n ov e v e Silent Valley Zone e # e # " L Wharfe un

L Bradford Supply # " Wetwang

Washburn # ! O

" # D

s u e

# r

we e e ! bl ! Dalton ib Brick nt # R House Farm # Holme " Aire Pennines ! on # Aylesby Derwent D sey # Valley Mer "

Lud#

t n

D e # r W

e T Celyn & r # r i Llanfair e we Dover t # Brenig ! ! ha D.C. av Alstonfield nt New m Erch Conwy " e Beck# # # # W # Red Dee Lion # D # ! # Weir Farm ove G Vyrnwy ! ! We nsu fi # m y Washpit D G Se Rutland Farm # ve ! # Clywedog rn Soa#r Stringside G Nuttalls ! Frying Pan Farm # Lodge y # ene Elan # Littl av e Ous W Brianne Valley Grafham G e " use Teme von O ! Dial # A # reat G W G Farm Y ye Redlands Hall # s # ! c # i ! i r Therfield w # Teifi y # Rectory Gauging Station (River name) T Col # Greenfield # U Col ne sk Garage " # n Farmoor ! Big Ampney " Mimram # Groundwater index well ! Tawe Cy # Stonor # non Five Crucis! Lee # Park G Pant y L ! Reservoir - individual am P London Lladron Rockley bo ang Thames " y ! ur # B dwa ! l Me n # a # " Bristol # c Reservoir - group (general location only) # k " Kennet w at ! Chipstead # Wimbleball A Great Clatworthy Tilshead e # B v r ! r Mol ! ue on t # Stour s Little Bucket Chalk West # e e T Farm G # Woodyates Itchen G G Compton Ardingly G O Bewl # # Manor us Jurassic limestones ! # # House #e T Tone aw St !! Chilgrove Houndean Exe our ! ! Lime P # House Bottom # r id # Permo-Triassic sandstones Roadford ! te Kiln Way dl ! t e # W G Bussells O al Westdean # ! # L l y in No.7A m gt No.3 Magnesian Limestone Colliford i on G # Ashton ngt # # on Tamar # Farm Warleggan D Carboniferous Limestone ar #Gannel t G Kenwyn Stithians © UUKCEH,KCEH ,BGS BG (2021).S (202 1©) Crown© Cro wcopyrightn copy.right

11 NHMP

The National Hydrological Monitoring Programme Water; supplementary rain gauges are operated by the Met (NHMP) was started in 1988 and is undertaken jointly by Office. The Met Office NCIC monthly rainfall series extend the UK Centre for Ecology & Hydrology (UKCEH) and back to 1910 and form the official source of UK areal rainfall the British Geological Survey (BGS). The NHMP aims to statistics which have been adopted by the NHMP. The provide an authoritative voice on hydrological conditions gridding technique used is described in Perry MC and Hollis throughout the UK, to place them in a historical context and, DM (2005) available at https://doi.org/10.1002/joc.1161 over time, identify and interpret any emerging hydrological trends. Hydrological analysis and interpretation within the Long-term averages are based on the period 1981-2010 and Programme is based on the data holdings of the National are derived from the monthly areal series. River Flow Archive (NRFA; maintained by UKCEH) and National Groundwater Level Archive (NGLA; maintained The regional figures for the current month in the hydrological by BGS), including rainfall, river flows, borehole levels, summaries are based on a limited rain gauge network so and reservoir stocks. these (and the associated return periods) should be regarded as a guide only. The Hydrological Summary is supported by the Natural Environment Research Council award number The monthly rainfall figures are provided by the Met Office NE/R016429/1 as part of the UK-SCAPE programme NCIC and are Crown Copyright and may not be passed on delivering National Capability. to, or published by, any unauthorised person or organisation.

For further details on rainfall or MORECS data, please Data Sources contact the Met Office:

Tel: 0870 900 0100 The NHMP depends on the active cooperation of many data Email: [email protected] suppliers. This cooperation is gratefully acknowledged. River flow and groundwater level data are provided by the Environment Agency (EA), Natural Resources Wales - Cyfoeth Naturiol Cymru (NRW), the Scottish Environment Enquiries Protection Agency (SEPA) and, for Northern Ireland, the Department for Infrastructure - Rivers and the Northern Enquiries should be directed to the NHMP: Ireland Environment Agency. In all cases the data are subject to revision following validation (high flow and Tel: 01491 692599 low flow data in particular may be subject to significant Email: [email protected] revision). A full catalogue of past Hydrological Summaries can be Details of reservoir stocks are provided by the Water accessed and downloaded at: Service Companies, the EA, Scottish Water and Northern Ireland Water. http://nrfa.ceh.ac.uk/monthly-hydrological-summary-uk

The Hydrological Summary and other NHMP outputs Some of the features displayed on the maps contained in may also refer to and/or map soil moisture data for the this report are based on the following data with permission UK. These data are provided by the Meteorological Office of the controller of HMSO. Rainfall and Evaporation Calculation System (MORECS). MORECS provides estimates of monthly soil moisture i. Ordnance Survey data. © Crown copyright and/or deficit in the form of averages over 40 x 40 km grid squares database right 2005. Licence no. 100017897. over Great Britain and Northern Ireland. The monthly time ii. Land and Property Services data. © Crown copyright series of data extends back to 1961. and database right, S&LA 145. iii. Met Office rainfall data. © Crown copyright. Rainfall data are provided by the Met Office. To allow better spatial differentiation the rainfall data for Britain All rights reserved. Unauthorised reproduction infringes are presented for the regional divisions of the precursor crown copyright and may lead to prosecution or civil organisations of the EA, NRW and SEPA. The areal proceedings. rainfall figures have been produced by the Met Office National Climate Information Centre (NCIC), and are Text and maps in this document are © UKCEH (2021) based on 5km resolution gridded data from rain gauges. unless otherwise stated and may not be reproduced without The majority of the full rain gauge network across the UK permission. is operated by the EA, NRW, SEPA and Northern Ireland

06/2021 12